Keeping Corrugated Sheets From Warping

Warp bending of corrugated sheets due to excess moisture.

Keeping corrugated sheets from warping. Therefore during production we should check the tension of the inner liner and the corrugated board and keep the tension of the facing and inner liners even. Reusable and paper faced on only one side. S warp board bows up on one corner and bows down on the opposite corner. Box loses its compression strength and collapses in stacking position.

Another culprit often actually more offensive is a natural contraction of pva the white glue or a water based filler during drying. Easy to use as you separate your warp layers. Some weavers prefer this over warping sticks. You need to consider the worst case of dimensional deformation.

Techniques for reducing moisture related warp include. Stable and consistent process and totally flat sheets of corrugated board coming out of the corrugator with more frequent quality changes and smaller order sizes. The causes of warpage are. Two valmet iq scanners for top and back side moisture measurement.

Fourth the main cause of warping the cause of warping is very complex summed up is due to the fact that noodle paper ie corrugated paper paper and paper in the production due to a variety of reasons caused by their expansion and contraction differences. Increase corrugator speed if possible adjust web and liner wrap either reduce double back wrap or increase. Diagonal or twist warp board curves along the diagonal of the sheet. The causes of cardboard warping.

Similarly excessive tension of the gluer will also lead to such a problem. This corrugated warp separator is perfect for keeping your yarn in line. Corrugated board for demanding customers the corrugated board we produce is often aimed at packaging requiring high quality printing which needs flat sheets and minimal impact on the outer liner to avoid washboard that effect on the print quality says ola lindberg process engineer at stora enso packaging in jönköping. Fast drying of corrugated sheet and its moisture resistance are two different concepts.

Down warp board bows down concave. There are very simple gauges made that are twelve inches wide with a small stylus in the middle to measure the deflection from the plane of the substrate. Gum which is drying fast need not have moisture resistance and vice a versa. As the tension of the single corrugated board and the facing liner is not even the tighter side will retract.

The present invention makes it possible to determine a warp in a corrugated cardboard sheet in a state in which the corrugated cardboard sheet is nearly finished and at an early stage and to correct the warp accurately and at an early stage on the basis of the warp determination. Order by the foot enough for your longest warp. Up warp board bows up convex. Yes warp is linear and can also be considered diagonal when measuring a corrugated sheet.

The nature and type of paper 2. Lets start with a note that despite popular belief it s not just water that causes the issue. If your longest warp is 15 yards order quantity would be 45.